refactor(jest-mock): Throw more descriptive error messages when tryin…

…g to mock a property
jestjs · SimenB · Jan 4, 2023 · Oct 23, 2022 · Oct 23, 2022 · Dec 19, 2022
commit c739864da5ddecd27a2eb5722ba543ccbccd1290
diff --git a/packages/jest-mock/src/__tests__/index.test.ts b/packages/jest-mock/src/__tests__/index.test.ts
@@ -1661,7 +1661,7 @@ describe('moduleMocker', () => {
         expect(() => {
           moduleMocker.mockProperty({method: () => {}}, 'method', () => {});
         }).toThrow(
-          'Cannot mock the method property because it is a function; use spyOn instead',
+          "Cannot mock the method property because it is a function. Use `jest.spyOn(object, 'method')` instead.",
         );
       });
 

diff --git a/packages/jest-mock/src/index.ts b/packages/jest-mock/src/index.ts
@@ -1361,15 +1361,19 @@ export class ModuleMocker {
       throw new Error(
         `Cannot mock the ${String(
           propertyKey,
-        )} property because it has a getter`,
+        )} property because it has a getter. Use \`jest.spyOn(object, '${String(
+          propertyKey,
+        )}', 'get').mockReturnValue(value)\` instead.`,
       );
     }
 
     if (descriptor.set !== undefined) {
       throw new Error(
         `Cannot mock the ${String(
           propertyKey,
-        )} property because it has a setter`,
+        )} property because it has a setter. Use \`jest.spyOn(object, '${String(
+          propertyKey,
+        )}', 'set').mockReturnValue(value)\` instead.`,
       );
     }
 
@@ -1387,7 +1391,9 @@ export class ModuleMocker {
       throw new Error(
         `Cannot mock the ${String(
           propertyKey,
-        )} property because it is a function; use spyOn instead`,
+        )} property because it is a function. Use \`jest.spyOn(object, '${String(
+          propertyKey,
+        )}')\` instead.`,
       );
     }